Wire up the getcpu cache system call on 32-bit ARM. Call the getcpu_cache_handle_notify_resume() function on return to userspace if TIF_NOTIFY_RESUME thread flag is set.
This provides an ABI improving the speed of a getcpu operation on ARM by skipping the getcpu system call on the fast path. Signed-off-by: Mathieu Desnoyers <mathieu.desnoy...@efficios.com> CC: Russell King <li...@arm.linux.org.uk> CC: Catalin Marinas <catalin.mari...@arm.com> CC: Will Deacon <will.dea...@arm.com> CC: Thomas Gleixner <t...@linutronix.de> CC: Paul Turner <p...@google.com> CC: Andrew Hunter <a...@google.com> CC: Peter Zijlstra <pet...@infradead.org> CC: Andy Lutomirski <l...@amacapital.net> CC: Andi Kleen <a...@firstfloor.org> CC: Dave Watson <davejwat...@fb.com> CC: Chris Lameter <c...@linux.com> CC: Ingo Molnar <mi...@redhat.com> CC: Ben Maurer <bmau...@fb.com> CC: Steven Rostedt <rost...@goodmis.org> CC: "Paul E. McKenney" <paul...@linux.vnet.ibm.com> CC: Josh Triplett <j...@joshtriplett.org> CC: Linus Torvalds <torva...@linux-foundation.org> CC: Andrew Morton <a...@linux-foundation.org> CC: Thomas Gleixner <t...@linutronix.de> CC: linux-...@vger.kernel.org --- arch/arm/include/uapi/asm/unistd.h | 1 + arch/arm/kernel/calls.S | 1 + arch/arm/kernel/signal.c | 1 + 3 files changed, 3 insertions(+) diff --git a/arch/arm/include/uapi/asm/unistd.h b/arch/arm/include/uapi/asm/unistd.h index 7a2a32a..6605e94 100644 --- a/arch/arm/include/uapi/asm/unistd.h +++ b/arch/arm/include/uapi/asm/unistd.h @@ -416,6 +416,7 @@ #define __NR_execveat (__NR_SYSCALL_BASE+387) #define __NR_userfaultfd (__NR_SYSCALL_BASE+388) #define __NR_membarrier (__NR_SYSCALL_BASE+389) +#define __NR_getcpu_cache (__NR_SYSCALL_BASE+390) /* * The following SWIs are ARM private. diff --git a/arch/arm/kernel/calls.S b/arch/arm/kernel/calls.S index fde6c88..6786411 100644 --- a/arch/arm/kernel/calls.S +++ b/arch/arm/kernel/calls.S @@ -399,6 +399,7 @@ CALL(sys_execveat) CALL(sys_userfaultfd) CALL(sys_membarrier) +/* 390 */ CALL(sys_getcpu_cache) #ifndef syscalls_counted .equ syscalls_padding, ((NR_syscalls + 3) & ~3) - NR_syscalls #define syscalls_counted diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c index 7b8f214..ff5052c 100644 --- a/arch/arm/kernel/signal.c +++ b/arch/arm/kernel/signal.c @@ -594,6 +594,7 @@ do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall) } else { clear_thread_flag(TIF_NOTIFY_RESUME); tracehook_notify_resume(regs); + getcpu_cache_handle_notify_resume(current); } } local_irq_disable(); -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/